Endless screen wire fabric and method of making same



July 19, 1938. H. KURTZ, 2,124,373

ENDLESS SCREEN WIRE FABRIC AND METHOD OF MAKING SAME Filed. Feb. 27, 1957 5 Sheets-Sheet 1 July 19, 1938. I I H. KURTZ 2,124,373

ENDLESS SCREEN WIRE FABRIC AND METHOD OF MAKING SAME Filed Feb. 27, 1937 :s sheets-sheet '2 AMA rig July 19, 1 938. v H. KURTZ ENDLESS SCREEN WIRE FABRIC METHOD OF MAKING SAME Filed Feb. 27, 1937 s Sheets-Sh et 3 Fly- F9- 9.

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' to all requirements, and the weld is made me Patented .luly 1 9,

" ENDLESS; SCREEN WIRE FABRIC AND METHOD OF MAKING SAME 1 karts-Karts, Reutlingen, Germany Application February 27, 1937, Serial No. 128,285

I-V Inger-many March 4, 1936 sea s. (of. 245-) My invention relates to endless screens ofmetal fabric, such as the Fourdrinier wires ofpapermaking machines, and, more particularly, to a method of connecting, by welding, two-ends of metal fabric, and tothe connection itself. M

It is an object of .my invention to providea method, and a connection, which are all suitable for fabrics of thethree end twill type. .Suchfabric is now frequently used, especially in the manufactureof journal paper.

Itiisfllgnown that endless screens of metal fabric, particularly for paper-making machines, are now obtained by welding together the ends of the warp wires projecting from the ends of the fabric.

In normal fabric, that is, in fabric whose warp wires are arranged above and below the weft.

wires in regular alternation, the present method of welding yields an endless screen which is equal short time.

However, when it is attempted to 'make a welded connection of this kind for a fabric of the three end twill type, the difliculty is that the warp wires which are arranged in groups of three, are

distributed irregularly over'the upper and'lower sides of the weft wires.

,According to my invention, this diiliculty is overcome as follows:

At one end of the threeend twill fabric, I erec't,

in each group of three warp wires, the outer end of at least one of the two wires which are below the last but one of the weft wires, preferably by pulling out the last weft wire at the end of the fabric in upward direction, place the two-ends of the fabric on a flat support or table, with the erectedwarp wire ends above the non-erected or horizontal ends of'the corresponding warp wires in the other end of the fabric, and weld the erected ends down onto the horizontal ones by meansyof a suitable welding torch, care being taken that metal not .involved in the' welding operation will not be overheated.

A very strong and durable connection is obtained if the two warp wires below the last but one weft wire are erected alternately in the ends of the fabric, sothat each erectedwarp wire in My invention will be more fully understood by reference to the accompanying drawings in which Figs. 1 to 3 are diagrams showing the position,

respectively; of the first, third, and central warp wire of a group with respect to a pair ofjaws and a roller for erecting the ends of the central 5 wires.

Figs. 4, 5, and 6 illustrate, respectively, the relative position of thetwo first, second or central,

and third wires of a group when the ends of the m fabric are in position for welding. Fig. 7 shows a portion of the connection, ready 'for'welding at the left, and-welded at the right.

Fig. 8 is a plan view.

Fig. 9'is a side elevation, partly in section on the line Hi -IX in Fig. 8, of a tool for erecting the ends of the second or central warp wires, and

.Fig. 10 is a diagram showing the operation of the tool. v

Referring now to the drawings, and first to 8 Fig.1, V is the frontend, and R is the rear end, of a fabric.

7 I" is the last weft wire but one in the front end, and 4' is the corresponding weft wire in the rear end. It will be remembered that the last weft wire in each fabric has been extracted for erecting the ends of the warp wires. It will also be remembered that the warp wires are arranged in three groups. Each group, as shown for the one at the extreme left of the fabric portion shown in Fig. '7, comprises the pair 30 of first wires I and 2 the pair of second or central wires 3 and 3', and the pair of third wires 1" and I Figs. 4, 5, and 6 show the wires of the individual pairs ready for welding. In the first pair, Fig. 4, the wire I is erected andfready to be welded down onto the horizontal wire 2" and, when the weld has been made, it is quite close to the weft wire V, at I, 2 in Fig. 7. The weld 3, 3 of the two central wires 3) and 3 is in an intermediate position with respect to the weft wires 4 and 4, and the weld 2, I of the third pair is quite close to the weft wire I. The continuous warp wires obtained by the welding together of the individual warp wires extend as follows with respect to the last-but-one weft wires: first pair, Fig- 4: from below 4" to above 4'; central pair, Fig. 5: from below 4' to below 4'; third pal?) Fig. 6: from above 4 to below 4*. The welding s'pots of the two outer pairs are equidistant fr'om the centrally positioned welding spot of the central pair. This symmetrical or staggered arrangement of the welding spots is very favorable, and the connection of the ends in this manner is excellent.

Referring now to Figs. 8 and 9, this tool was -to rotate about a pivot G. The pivot is threaded at one end, H, and inserted in a female thread in 'the corresponding shank of the fork E.

v The flanged roller F has a set of perimetral flutes K, as best seen in the diagram Fig. 10. The flutes define teeth L, .each with a step M below, and a ridge N at its crest. The pitch of the teeth L is so determined that each tooth jumps two warp wires, and engages the third.

In operation, the end of the fabric is placed in a gap between two jaws A and B, lHgs. 1 to 3, whose upper faces are inclined, the face of the jaw B projecting beyond that of the jaw A for about the thickness of a wire. The roller F is placed on the face of the jaw B with its plain portion, its fluted portion extending beyond the gap between the jaws, vFig. l. A track C is formed on the jaw B, for the flange O of the roller F. After the warp wires have been erected by pulling out the last weft, as described, the fabric is placed between the jaws and the roller F is moved along its track C-in parallel relation to the weft wires-by means of handle D. Fig. 1 shows an erected wire I which is obviously not interfered with by the teeth L of"the roller F, since the jaw Bis higher than the jaw A. Nor is the horizontal wire 2' interfered with, as the teeth are pitched to jump two wires. But the wire 3 is engaged by the step M while the ridge N prevents slipping of the tooth on the wire. In this manner, all central wires of the individual ,groups are erected.

As mentioned in the introduction, it' is im-" portant that at least one of the two wires below the last but. one weft wire 4' or 4', should be erected, at least at one end of the fabric. With .certain methods of welding, the ends of the fabric are so positioned with respect to each other that two of the wires in each group are ready for welding together at both ends of the fabric without preparation, and only the third wire, for instance the central wire 3', 3',.wants erecting. Or it is possible that only one of the wires in the first or third pair must be erected, as shown in Figs. 4 and 6, and the corresponding wire in the other end remains horizontal.

I have described the erection of certain warp wires by pulling out the last weft wire, but I may erect any wires in any other suitable way. I have described the erection of the central wires 3 by means of the fluted roller F. In this operation, the roller is moved along the weft wires in a given direction. If it is desired to erect an-- other set of wires in a similar manner, the wheel or roller F is replaced by another roller whose teeth L, as shown in dotted lines in Fig. 10, are reflected images'of the teeth L, the position of the crests and ridges M, N being the reverse of that in the teeth L. This "reflected image roller is moved along the wefts in the opposite direction. I

I claim:

1. The method of making endless screens of three end twill wire fabric having warp wires arranged in' groups of three, comprising in removing a weft wire at one end of the screen and erecting at least one of two warp wires in each group which are below the said removed weft wire of the other end of the fabric, and weldingthe upturned warp wire down onto the horizontally alined warp wire of the other end of the fabric.

2. The method of making endless screens of three end twill wire fabric having warp wires arranged in groups of three, comprising in removing a weft wire at one end of the screen and erecting two warp'wires in each group which are below the last removed weft wire at the ends of the fabric, placing the erected wires in registering relation in both ends of the fabric, and welding them together to connect the ends of the screen.

3. The method of making endless'screens of three end twill wire fabric having warp wiresarranged in groups of three, comprising erecting the central warp wires in each group disposed at both ends of the fabric, placing them in registering alined relation, and welding them together to connect the ends of the screen. 0

4. The method of making endless screens of three end twill wire fabric having warp wires arranged in groups of three, comprising in re- -movlng a weft wire at one end of the screen and 5. An endless screen of three end twill wire fabric comprising warp wires arranged in groups of three, said warp wires being welded together at the ends of the fabric in staggered arrangement of the welded wire ends to connect the ends of the screen fabric.

6. An endless screen of three endtwill wire fabric comprising warp wires arranged in groups of three, said warp wires being welded together .at the ends of the fabric; an intermediate welded connection of each pair of central wires of each group, said intermediate welded connection being positioned centrally between the space of the two last with one removed weft wires at the ends of the fabric, and each pair of first and third alined wires being welded at points opposite with respect to, and equidistant from, the point where the central wires of each group are welded together. g

'l. The method of making endless screens of wire fabric .having warp threads arranged in groups of three, which consists in removing the last weft wire at one end of the screen, and welding the ends of the warp wires together with the welded points of the warp wires of each group arranged in staggered relation.

8. The method of making endless screens of wire fabric having warp threads arranged in groups of three, which consists in removing the last weft wire at one end of the screen, and welding the ends of the warp wires of each group together with the welded points of each group -arra.nged in diagonal relation to the length of the screen.

HANS 

